noun
triumphal arch; arch of triumph
Refers to a monumental arch built to commemorate a victory. Often used in proper names like エトワール凱旋門 (Arc de Triomphe de l'Étoile).
パリの凱旋門は有名な観光名所だ。
The Arc de Triomphe in Paris is a famous tourist attraction.
From 凱旋 (triumphant return) + 門 (gate).